Wednesday, March 03, 2010
"Moore's Law" for fusion
In our departmental colloquium today, the speaker talked about calculations he's been doing on energy dissipation due to turbulence in controlled fusion experiments. Much of the talk was very dry, but I thought this figure from his introduction was really interesting. (I googled it.)
He acknowledged that sometimes fusion is considered to be a laughing stock because for the past 50 years, a working fusion reactor has always been "30 years away". But while the progress has not been as anticipated, one thing that I hadn't realized is how consistent the progress has been.
What the graph shows, is that in order to have self-sustaining fusion, the "triple product", the product of the density (n), temperature (T), and time of reaction (tau), needs to be above a certain threshold. The upper left line shows that progress towards that threshold has very consistently been increasing at an exponential rate. One can compare that to the "Moore's Law" progress in computer chips shown as the red line. The speaker was confident that since the trend of constant progress towards the required triple product has shown no sign of halting, self-sustaining fusion really would occur in the immediate future (10 years, he said). Functioning commercial power plants would of course be many years after that.
He acknowledged that sometimes fusion is considered to be a laughing stock because for the past 50 years, a working fusion reactor has always been "30 years away". But while the progress has not been as anticipated, one thing that I hadn't realized is how consistent the progress has been.
What the graph shows, is that in order to have self-sustaining fusion, the "triple product", the product of the density (n), temperature (T), and time of reaction (tau), needs to be above a certain threshold. The upper left line shows that progress towards that threshold has very consistently been increasing at an exponential rate. One can compare that to the "Moore's Law" progress in computer chips shown as the red line. The speaker was confident that since the trend of constant progress towards the required triple product has shown no sign of halting, self-sustaining fusion really would occur in the immediate future (10 years, he said). Functioning commercial power plants would of course be many years after that.
# posted by John Colton @ 5:50 PM 
